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Rethinking
food production for a world of eight billion
Lester
R. Brown
(July 22, 2009) In April 2005, the World Food Programme
and the Chinese government jointly announced that food aid
shipments to China would stop at the end of the year. For a
country where a generation ago hundreds of millions of
people were chronically hungry, this was a landmark
achievement. Not only has China ended its dependence on food
aid, but almost overnight it has become the worlds third
largest food aid donor.
The key to Chinas success was the economic reforms in 1978
that dismantled its system of agricultural collectives,
known as production teams, and replaced them with family
farms. In each village, the land was allocated among
families, giving them long-term leases on their piece of
land. The move harnessed the energy and ingenuity of Chinas
rural population, raising the grain harvest by half from
1977 to 1986. With its fast-expanding economy raising
incomes, with population growth slowing, and with the grain
harvest climbing, China eradicated most of its hunger in
less than a decade--in fact, it eradicated more hunger in a
shorter period of time than any country in history.
While hunger has been disappearing in China, it has been
spreading throughout much of the developing world, notably
sub-Saharan Africa and parts of the Indian subcontinent. As
a result, the number of people in developing countries who
are hungry has increased from a recent historical low of 800
million in 1996 to over 1 billion today. Part of this recent
rise can be attributed to higher food prices and the global
economic crisis. In the absence of strong leadership, the
number of hungry people in the world will rise even further,
with children suffering the most.
Dealing with this problem requires addressing the long-term
trends leading to growth in demand for food outpacing growth
in supply. One key to the threefold expansion in the world
grain harvest since 1950 was the rapid adoption in some
developing countries of high-yielding wheats and rices
(originally developed in Japan) and hybrid corn (from the
United States). The spread of these highly productive seeds,
combined with a tripling of irrigated area and an 11-fold
increase in world fertilizer use, tripled the world grain
harvest. Growth in irrigation and fertilizer use essentially
removed soil moisture and nutrient constraints on much of
the worlds cropland.
Now the outlook is changing. Farmers are faced with
shrinking supplies of irrigation water, a diminishing
response to additional fertilizer use, rising temperatures
from global warming, the loss of cropland to nonfarm uses,
rising fuel costs, and a dwindling backlog of yield-raising
technologies. At the same time, they also face fast-growing
demand for farm products from the annual addition of 79
million people a year, the desire of some 3 billion people
to consume more livestock products, and the millions of
motorists turning to crop-based fuels to supplement
tightening supplies of gasoline and diesel fuel. Farmers and
agronomists are now being thoroughly challenged.
The shrinking backlog of unused agricultural technology and
the associated loss of momentum in raising cropland
productivity are found worldwide. Between 1950 and 1990,
world grain yield per hectare climbed by 2.1 percent a year,
ensuring rapid growth in the world grain harvest. From 1990
to 2008, however, it rose only 1.3 percent annually. This is
partly because the yield response to the additional
application of fertilizer is diminishing and partly because
irrigation water is limited.
This calls for fresh thinking on how to raise cropland
productivity. One way is to breed crops that are more
tolerant of drought and cold. U.S. corn breeders have
developed corn varieties that are more drought-tolerant,
enabling corn production to move westward into Kansas,
Nebraska, and South Dakota. Kansas, the leading U.S.
wheat-producing state, has used a combination of
drought-resistant varieties in some areas and irrigation in
others to expand corn planting to where the state now
produces more corn than wheat.
Another way of raising land productivity, where soil
moisture permits, is to increase the area of multicropped
land that produces more than one crop per year. Indeed, the
tripling in the world grain harvest since 1950 is due in
part to impressive increases in multiple cropping in Asia.
Some of the more common combinations are wheat and corn in
northern China, wheat and rice in northern India, and the
double or triple cropping of rice in southern China and
southern India.
The spread in double cropping of winter wheat and corn on
the North China Plain helped boost Chinas grain production
to where it rivaled that of the United States. Winter wheat
grown there yields 5 tons per hectare. Corn also averages 5
tons. Together these two crops, grown in rotation, can yield
10 tons per hectare per year. Chinas double cropped rice
annually yields 8 tons per hectare.
Forty years ago, North India produced only wheat, but with
the advent of the earlier maturing high-yielding wheats and
rices, wheat could be harvested in time to plant rice. This
wheat/rice combination is now widely used throughout the
Punjab, Haryana, and parts of Uttar Pradesh. This practice
yields a combined 5 tons of grain per hectare, helping to
feed Indias 1.2 billion people.
A concerted U.S. effort to both breed earlier maturing
varieties and develop cultural practices that would
facilitate multiple cropping could substantially boost crop
output. If Chinas farmers can extensively double crop wheat
and corn, then U.S. farmers could do the same if
agricultural research and farm policy were reoriented to
support it.
Elsewhere, Western Europe, with its mild winters and
high-yielding winter wheat, might also be able to double
crop more with a summer grain, such as corn, or with a
winter oilseed crop. Brazil and Argentina have an extended
frost-free growing season that supports extensive
multicropping, often wheat or corn with soybeans.
In many countries, including the United States, most of
those in Western Europe, and Japan, fertilizer use has
reached a level where using more has little effect on crop
yields. There are still some places, however, such as most
of Africa, where additional fertilizer would help boost
yields. Unfortunately, sub-Saharan Africa lacks the
infrastructure to transport fertilizer economically to the
villages where it is needed. As a result of nutrient
depletion, grain yields in much of sub-Saharan Africa are
stagnating.
One encouraging response to this situation in Africa is the
simultaneous planting of grain and leguminous trees. At
first the trees grow slowly, permitting the grain crop to
mature and be harvested; then the saplings grow quickly to
several feet in height, dropping leaves that provide
nitrogen and organic matter, both sorely needed in African
soils. The wood is then cut and used for fuel. This simple,
locally adapted technology, developed by scientists at the
International Centre for Research in Agroforestry in
Nairobi, has enabled farmers to double their grain yields
within a matter of years as soil fertility builds.
Despite local advances, the overall loss of momentum in
expanding food production is unmistakable. It will force us
to think more seriously about stabilizing population, moving
down the food chain, and using the existing harvest more
productively. Achieving an acceptable worldwide balance
between food and people may now depend on stabilizing
population as soon as possible, reducing the unhealthily
high consumption of animal products among the affluent, and
restricting the conversion of food crops to automotive
fuels. It also calls for a concerted effort to raise water
use productivity, similar to the gains achieved for land
use, and to stabilize climate to avoid crop-withering
temperatures and more frequent droughts. These efforts
combined can help put us on the path to ensuring enough food
for all.
Lester Brown is founder and president of the Earth
Policy Institute. This article was adapted from Chapter 9,
Feeding Eight Billion Well, in Lester R. Brown, Plan B
3.0: Mobilizing to Save Civilization (New York: W.W. Norton
& Company, 2008), available for free downloading and
purchase at www.earthpolicy.org/Books/PB3/index.htm
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